Tocagen, Inc. is a clinical-stage, cancer-selective gene therapy compan. It focuses on the development of product candidates designed to activate a patient's immune system against their own cancer from within. It is in the business of discovery, development, and commercialization of products for the treatment of cancer. The company was founded by Thomas E. Darcy, Harry E. Gruber, Douglas J. Jolly, and Dennis N. Berman in August 2007 and is headquartered San Diego, CA.